Ecrinesomus co-occurred with the relatively similar looking Bobasatrania. Fossils of these two genera are sometimes misidentified, but can be distinguished based on the following characters: the number of scale rows (Ecrinesomus has ca. 48 transversal scale rows, Bobasatrania has fewer), the body shape (Ecrinesomus has an elliptical, Bobasatrania a rhombic body outline) and the distinct skull bone pattern.[3]
^Lehman, Jean-Pierre (1956). "Compléments à l'étude des genres Ecrinesomus et Bobasatrania de l'Eotrias de Madagascar". Annales de Paléontologie (in French). 42: 67–94..